If the depression's circulation strengthens, producing maximum sustained winds of 39 mph to 73 mph, then it will be upgraded to a tropical storm. A tropical storm causes stronger and more damaging wind gusts, heavier and more prolonged rain and flooding, as well as higher storm surge.

If the system further strengthens to 74 mph or greater, it is then classified as a hurricane. Hurricanes have five categories of their own based on wind strength.